The Safety and Tolerability of Ferric Citrate as a Phosphate Binder in Dialysis Patients

Background: A phase II open-label study was conducted in hemodialysis patients evaluating the short-term safety, tolerability, and iron absorption with ferric citrate when used as a phosphate binder. Methods: Enrollment occurred in two periods. Period 1 recruited patients taking 6–15 pills/day of binder with phosphorus of ≥2.5 mg/dl. Period 2 recruited patients taking ≥12 pills/day of binder with phosphorus of ≥3.5 mg/dl. Participants with ferritin ≥1,000 µg/l or transferrin iron saturation (TSAT) ≥50% at screening were excluded. Subjects discontinued their previous binders and started 4.5 g/day of ferric citrate (period 1) or 6 g/day (period 2) and were titrated for 4 weeks to maintain a phosphorus of 3.5–5.5 mg/dl. Chemistries and complete blood count were obtained weekly and a gastrointestinal questionnaire was administered at drug initiation and final visit. Iron therapy was permitted if the ferritin was